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A Monascus ruber strain was isolated that was able to grow on mineral medium at high sugar concentrations and 175 g/l lactic acid at pH 2.8.

A Monascus ruber strain was isolated that was able to grow on mineral medium at high sugar concentrations and 175 g/l lactic acid at pH 2.8., A Monascus ruber strain was isolated that was able to grow on mineral medium at high sugar concentrations and 175 g/l lactic acid at pH 2.8.

A multi-block copolymer comprises at least one hydrophilic collagen-like block and at least one silk-like block. The silk-like block comprises an amino acid sequence ((GA) m GX) n , wherein G is glycine, A is alanine, m and n are at least 2. X is an ionizable amino acid. The ionizable amino acid is inducible to bear a positive charge or a negative charge. The ionizable amino acid bearing the positive charge is preferably histidine and the one bearing the negative charge is preferably glutamic acid.

Disclosed is a block co-polypeptide comprising at least two blocks T and at least one block S, with blocks T and S alternating, wherein each T independently denotes a Trimerizing Block being a polypeptide block capable of forming a thermoreversible collagen-like triple helix structure, and whereineach S independently denotes a Spacer Block S being a polypeptide neither forming a collagen-like triple helix. The block co-polypeptide is capable of forming a gel, and is useful as an animal-free, biocompatible substitute for gelatin. Uniquely, the polypeptide allows the independent controlling of the melting temperature of the gel, the stiffness and crosslink density of the gel, the lower critical gel-forming concentration related to the length of the molecules, and unrelated (e.g. biological, physiological, pharmaceutical or signalling) functions of the molecule.

Elastin-like polypeptides (ELPs) are biocompatible designer polypeptides with inverse temperature transition behavior in solution. They have a wide variety of possible applications and a potential medical importance. Currently, production of ELPs is done at lab scale in Escherichia coli shake flask cultures. With a view to future large scale production, we demonstrate secreted production of ELPs in methanol-induced fed-batch cultures of Pichia pastoris and purification directly from the culture medium. The production of ELPs by P. pastoris proved to be pH dependent within the experimental pH range of pH 3 to 7, as an increasing yield was found in cultures grown at higher pH. Because ELP produced at pH 7 was partly degraded, a pH optimum for production of ELP was found at pH 6 with a yield of 255 mg of purified intact ELP per liter of cell-free medium

De Biobased-Productsdivisie van AFSG-Wageningen UR gebruikt micro-organismen om op commando polymeren te maken met een van a tot z ontworpen monomeervolgorde en blokstructuur

Heterologous proteins secreted by yeast and fungal expression hosts are occasionally degraded at basic amino acids. We cloned Pichia pastoris homologs of the Saccharomyces cerevisiae basic residue-specific endoproteases Kex2 and Yps1 to evaluate their involvement in the degradation of a secreted mammalian gelatin. Disruption of the P. pastoris KEX2 gene prevented proteolysis of the foreign protein at specific monoarginylic sites. The S. cerevisiae -factor preproleader used to direct high-level gelatin secretion was correctly processed at its dibasic site in the absence of the prototypical proprotein convertase Kex2. Disruption of the YPS1 gene had no effect on gelatin degradation or processing of the -factor propeptide. When both the KEX2 and YPS1 genes were disrupted, correct precursor maturation no longer occurred. The different substrate specificities of both proteases and their mutual redundancy for propeptide processing indicate that P. pastoris kex2 and yps1 single-gene disruptants can be used for the -factor leader-directed secretion of heterologous proteins otherwise degraded at basic residues.

The present invention relates to a method for the production of collagen-like compounds containing hydroxylated proline residues. Of specific interest is the production of recombinant collagen-like compounds in which hydroxylation of proline residues is achieved by a prolyl hydroxylase from a fungus, preferably a yeast, in particular Hansenula polymorpha. Also the invention concerns a method for controlling the hydroxylation of proline residues by such a prolyl hydroxylase characterised by the addition of collagen-like oligopeptides, such as gelatine hydrolysate, in particular gelatone or peptone.

A tabular silver halide emulsion wherein the tabular grains account for more than 75% of the total grain projected area said emulsion comprising silver halide grains nucleated in the presence of nucleation peptizer and thereafter grown in the presence of growth peptizer, wherein at least one of the peptizers is substantially pure collagen like material prepared by genetic engineering of native collagen encoding nucleic acid, said peptizer having an amino acid sequence comprising more than 4 different amino acids. A process of preparing the AgX emulsion. A process of producing recombinant collagen like polypeptide comprising expression of a collagen like polypeptide encoding nucleic acid sequence by a microorganism to a degree exceeding 0.95 grammes /liter, said recombinant collagen being free of helix structure and preferably the expression occurring in a microorganism other than E. coli or Saccaromyces cerevisiae.